vapoursource: Remove unsued variable

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Merge pull request #132 from dwbuiten/static_analysis

vapoursource: Remove unsued variable
vapoursource: Provide _AbsoluteTime metadata

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>